[Tagging] What about a disused quarry and historic surface mining?

[Tom Pfeifer]

On 10.01.2017 10:47, Zecke wrote:
>
>> Artificial rock faces in quarries and open pit mines, called berms,
>> are created due to blasting. The faces are typically inclined 60-70°
>> with drops of max. a few tenth of meters. This fundamental difference
>> might be best taken into account by using man_made=embankment for these.
>
> I have to contradict in one point. I know of a lot of former and present
> quarries where the faces are inclined 90° and ten'ths of meters high.
> Maybe this is not so much the point for open pit mines. But tagging
> should be ready to cope with non-natural steep faces. I see no problem
> however in using some man_made key for this. "embankment" might be
> misleading, however. What about man_made=cliff for non-natural steep drops?
>
> The renderer then could decide whether to choose differentiating
> drawing. (Most probably he won't do so).

Yes, the OSM-definition for man_made=embankment covers other purposes 
and should not be used for a cliff in a current or former quarry.

I would not be in favour of a new man_made=cliff tag, since it was not 
man's intention to erect e cliff, it was the intention to dig out the 
material. I still see natural=cliff applicable, combined with a sub-tag 
if needed.

As for the angles, I have climbed on cliffs formed by erosion (includung 
sea cliffs) and in former quarries, which can have all angles from 
leaning, vertical to overhanging.

tom